The Killer Caimans are the product of selective breeding by the lizard people over several centuries. Once rather harmless caimans, today resilient beasts - the selection changed them according to the whims of their lizard masters. In ancient times, the caiman breeding was a pastime of the royalty and a strong caiman was a vital prestige object. Caiman battles were arranged to show off and to settle conflicts. Over the years, caimans escaped or were given as present to loyal subjects who set them free or interbred them with escaped beasts. This way, they slowly found their way back into the wilds. Later lower caste lizards captured them and they became widespread pets.

The Killer Caiman that is found nowadays in Zao has surpassed its ancestors in all ways. As if they weren't already dangerous enough, the royalty of the lizard people still possesses caiman hatcheries where they breed even stronger and more resilient versions of the Killer Caiman.